Marker protein may help breast cancer screening

EGFR can show up 17 months before disease appears

High concentrations of a protein implicated in several cancers may be an early warning sign of undiagnosed breast cancer, a new study suggests. Blood samples taken months before breast cancer was diagnosed show the receptor was elevated more often in women with the disease than in women who didn’t develop breast cancer, scientists reported April 20 at a meeting of the American Association for Cancer Research.

Although the marker isn’t a sure indication of incipient breast cancer, it might eventually contribute to that diagnosis, said study coauthor Christopher Li, a physician and epidemiologist at the Fred Hutchinson Cancer Research Center in Seattle who presented the findings. “There is considerable investment in trying to discover this disease while it is most treatable,” he said.

Li and his colleagues analyzed blood samples obtained from 688 women who had developed breast cancer while participating in a large medical trial and from 688 others in the trial who hadn’t developed cancer. The two groups were matched for race, ethnicity and age.

The blood samples had been drawn from the cancer patients up to 17 months before their diagnosis. The researchers focused on EGFR, or epidermal growth factor receptor, a cell-surface receptor protein that can trigger pro-growth behavior in a cell, such as proliferation, survival and migration.

Women with the highest levels of EGFR were nearly three times as likely to develop breast cancer as were women with the lowest levels. Among women who were taking estrogen and progesterone for menopausal hormone therapy at the time their blood was drawn, those with the highest EGFR levels were nine times as likely to developing breast cancer compared to women with the lowest EGFR levels.